Ejector



Patented Dec. 1, 1925.

UNITED STATE S;P"A"T;E'NT caries.

'GOTTDANK L. KO'IHNY, OI STRAFIORD, PENNSYLVANIA, ASSIGNOB TO 0. n. WHEELER MANUFACTURING COMPANY, TION OF PENNSYLVANIA.

OI PHILADELPHIA, PENNSYLVANIA, A 00320m-- EJECTOR.

KornrzY,

' I which the following is a specification.

--My invention relates to ejectors utilizable 'for raising the pressure of one fluid .by

1 another, and particularly for. raising the pressure of elastic fluid, asair or va or exhausted from a steam condenser, by e astic motive fluid, as steam. My invention relates moroparticularly 16 to improvements in ejectors of the type comprising annular or radial nozzle and difliuser structures, of the character described and claimed in prior Letters Patent of the United States No. 1,282,595, October In accordance with my invention, the spaced nozzle members have at their peri heries considerable or substantial width or thickness, effecting a' surrounding region 2 or zone into which neither the motive fluid nor the fluid to be com ressed enters, and in any event, in which t e motive fluid and fluid to be compressed do not come into contact, mixture or entraining relation with each other; and causing the motive fluid jet and fluid to be compressed to come into contact or entnaining relation at a substantial distance radially outward from the peripheries of the nozz e members, thereby preventing disturbance or surface rupture of the jet immediately adjacent the outlet of: the nozzle, and in general, effecting improvement in character of approach to each other of the motive "fluid and the fluid to be compressed, with resultant increase in the amount of fluid compressed, for a given amount of motive fluid utilized. Further in accordance with my invention, I'jprovide 'for she. fluid to be com-' pressed anannular passage, between each of the nozzle members and the associated difi'user'member, which is itself in effect a convergent nozzle passage, whose cross section is always decreasingas the; passage progresses axially and radially,,the change of cross section prefiera-bly being sul'istantially uniform, and inany event not increasing in cross section after a preceding decrease in cross section.

Application filed m '26,

apparatus embodying my invention.

are members spaced from each other to form of themembcrs C and C Upon t 1924. semi no. 728,308

My invention resides in the features of 68 structure, proportionment and combination of the character hereinafter described and claimed. X v 1 For an understanding of m invention, and for an'illustration of one o the various forms it may take, reference is tobe had to the accompanying drawing, in whichi Fig. 1 is a cross sectional view of ejector ig. 2- is .a fragmentary cross sectional view, on enlarged scale.

Fig. 3 is a curve illustrating a characteristic of my improvemen.

. Referring to Figs. 1 and 2, C and C between their adjacent faces the nozzle passage N of the annular nozzle structure with which coac'ts the diffuser structure comrising the annular diffuser members H and spaced axially from each other to form the ifi'user passage D, which is convergent divergent, outwardly, with the throat or ie 'on of smallest cross section at 9. a

he motive fluid, as steam or equivalent,

is introduced into the assage A within the nozzle member C wit in which is formed also the throat T of the motive-fluid-expanding nozzle structure, beyond which the nozzle passage N increases in cross section outwardly to the nozzle outlet at the eriphery e PPQ ing nozzle member 0 may be provided the a central tip or point t,

The cross section of the throat Ti's constant, therefore passing, at agiven. re'ssure, a constant amount of motive flui However, the point t may be of vsuch length as to project into or be adjustable into -,the throat T, in which latter case the amount of motive fluid is variable. v

The motive fluid passes outwardly radial ly in all directions in the form of a disk or sheet, emerging from the nozzle assage' N' in a free jet directed into the diffuser passage D. 1

The air, vapor or mixture of them, or other fluid to be compressed or raised --in ressure, enters at the suction port S, and 1S delivered through the passages p, to the annular chambers 13 and B which. ave the annular convergent outlet or delivery passages P and P respectively.

pressed come into contact or entrained re lation and pass outwardly in combination or in mixture through the diiiuser passage D, within which they lose in velocity and gain in pressure. ly discharged into the circumferential or annular discharge passage or casing E, from which it emerges through the discharge port F.

The nozzle-forming members C and C have at their peripheries substantial widths or thickness as indicated at w, from which theperipheral surfaces of the nozzle members fallIa-way in the curves v, the periphcries of the nozzle members in their portions indicated at o bein of relatively great diameters, and considerably greater than in the case of the'corresponding members of the aforesaidPatent'1,282,595.

The radially flowing free jet issuing from the nozzlle passages N is projected a considerable distance beyond the peripheral portions w of the nozzle members, and, as indicated, well into the mouth of the diffuser passage D. Surrounding the portions -w of the nozzle membersare formed the regions y, of high vacuum or practically devoid of fluid, the surfaces '0 being so directed as to guide the incoming air or other fiuid to becompressed past the peripheries w of the nozzle members, the motive fluid jet and thefiuid' to be entrained coming into entraine mg relation or contact as at 2, preferably well within themouth of the diffuser passage. In 'other words, the tangent to the curve a at the periphery w is inclined to the inner face of the nozzle member, whereby the fluid passing along the surfaceo and beyond the periphery w will come into entraining relation with the free jet only as a substantial distance radially beyond the periphery w. The radial jet issuing from the nozzle N is free and undisturbed as it issues from the nozzle passage, and the fluid to be entrained is guided in such path into contact or entraining relation with the jet that on the whole an appreciable improvement in economy or operation of the ejector is attained.

Correlated with the exterior nozzle surfaces 4; are the surfaces as on the difiuser members H and H forming with the surfaces 4; the annular passages P and P which, while they advance axially and radially outwardly, decreases in cross section, forming substantially an annular convergent nozzle passage in which the air or other fluid to be entrained increases in velocity and thereafter comes into. contact or entraining relation with the motive fluid The passages P and P may be said to have stream lines, of which, forexample, the medium stream line is indicated at m, Fig. 2, normal to which are the passage widths o, 0

The mixture is eventnalthan unlform. It is desirable, however, that nowhere along the line m shall the cross sectional area of the passage P increase as compared with any preceding position along the line 1 With the blunt or thick edges w at the peripheries of the nozzle members, effecting the dead or empty zones or regions 11 and by additionally employing the stream line passages such as P and P diminishing continuously or substantially uniformly in cross sectional area along a medium stream line, it is possible for a given sized ejector or utilizing a given amount of steam or motivefiuid materially to increase the number of pounds of air compressed, as will become apparent from an examination of the example indicated in Fig. 3, in which abscissae are absolute suction pressures in inches of mercury and whose ordinates are pounds of free air per hour raised in pres- I sure by the. ejector. The dotted curve a is the charactepistic or indicates the performance of an ejector of the type disclosed in the aforesaid prior Patent 1,282,595, and

is the fact that at the various suction pres- 1 sures the improved ejector compresses a greater number of pounds of air per hour. For example, with a suction pressure of three inches, he old ejector compresses about twenty pounds of air per hour, while with my improvement, with the same suction pressure, about fifty pounds of air are com.-'

pressed per hour. And throughout a range of suction pressures up to six inches and even higher, the improved ejector will compress a greater amountof air per hour for the same motive fluid consumption. Accordingly, with in improvement the efiiciency or economy 0 .the ejector is materially or substantially improved.

have substantially no effect upon the pas-' sage P. a

Further in accordance with my invention,

the passages, particularly P and P are symmetrical on opposite sides of the median planes 0 and d, which is not true of the apparatus disclosed in the aforesaid Letters- Patent 1,282,595, in which also there was generally an offset of the motive fluid jet to one side of the median line or plane of the diffuser passage.

In accordance with my improvement, the

need for adjustment of the nozzle member C is materially less, and such adjustment as is made is merely to effectthe correct width of nozzle passage N, and with this adjustment made, even prior to operation or test,

it generally will be found upon operation ortest that no further adjustment is necessary and the apparatus will operate at its best.

The practically complete or perfect symmetry of the passages P and P. on opposite sides of the median planes 0 and d, and the substantially perfect coincidence of the' median planes 0 and d of the nozzle and vantage.

diffuser passages is of practical importance in utilizing the motive fluid to maximum ad- While I have shown and described my in- "ention in its preferred form in which the 'nozzleand diffuser passages are normal to the axis of the annular nozzle and annular diffuser, it will be understood thatmy 1nvention is applicable also to the case where these passages are not normal to the axis, but are more or less inclined with respect thereto, I as described as a possible arrangement or construction in the aforesaid Letters Patent No. 1,282,595.

It will be understood also that a pluralityof ejectors of the character herein described may be connected in series or tandem with each other to form a multi-stage ejector of any suitable number of stages,'and that any suitable number of the stages of the multiple stage arrangement may comprise a tubular ejector. Y

It will be understood -further that the.

-width of the nozzle passage N and the width of the diffuser throat 9 may be related to each other in any suitable way, the width of the throat q, however, preferably being smaller than the width ofthe'nozzle passage N, as described in the aforesaid Letters Patent. It is preferred also that the area of the nozzle passage N at its outlet'be greater than the cross sectional area of the diffuser passage at its throat g, as described in the aforesaid Letters Patent, though it will. be understood that any other suitable relations are comprehended within my present invention.

WVhat I claim is :1

1. A member of an annular nozzle having its periphery of greatest diameter adjacent.

terminating at said periphery of greatest diameter. 2. A member of an annular nozzle having its periphery of greatest diameter adjacent that face thereof whichforms awall of thenozzle passage, and having a peripheral fluid-guiding surfaceof relatively great diameter curving axially and outwardly and terminating at said periphery of greatest diameter, said peripheryof greatest diameter having substantial axial width or thickness. 3. A member of an annular nozzle having its periphery of greatest diameter adjacent that face thereof which forms a wall of the nozzle passage, and having a peripheral fluid-guiding surface of relatively great diameter curving axially and outwardly and terminating at said periphery of greatest diameter, the tangent to the curve of said' fluid-guiding surface at said periphery being substantially inclined with respect to said face, said periphery of greatest diameter having substantial axial width or thickness.

4. Anannular motive fluid nozzle comprising members spaced from each other to form a nozzle passage, said nozzle members having at their peripheries of maximumdiameter substantial axially, and each of said members having curvedfluid-guiding surfaces of relatively great diameter disposed symmetrically on opposite sides of the median plane of the nozzle passage, said surfaces at said peripheries being inclined to the walls of the nozzle passage to effect dead spaces beyond said peripheries of maximum diameter.

5. Ejector apparatus comprising annular width or thickness diffuser and nozzle structures, said nozzle structure comprising nozzle members spaced from each other to form a nozzle passage, said nozzle members having exterior fluidguiding surfaces disposed at relatively great distances from thenozzle axis, said diffuser structure comprising annular diffuser members spaced from each other and having adjacent the inlet end of the diffuser passage curved fluid-guiding surfaces which with said surfaces on said nozzle structure form stream line passages delivering the fluid to be entrained to the jet issuing from said nozzle passage.

6. Ejector apparatus comprising annular diffuser and nozzle structures, said nozzle structure comprising nozzle members spaced from each other to form a nozzle passage,

said nozzle members having exterior fluid- 5 guiding surfaces disposed at relatively great distances from the nozzle axis, said difiuser structure comprising annular diffuser members spaced from each other and having adjacent the inlet end of the diffuser passage curved fluid-guiding surfaces whichwith said surfaces on said nozzle structure form stream line passages delivering the fluid to be entrained to the jet issuing from said nozzle passage, the median planesof the nozzle and diffuser passages being substantially coincident and said fluid-guiding passages being symmetrical on oppos te sides of said planes. i

7. Ejectorfapparatus comprising annular diffuser? and nozzle structures, said nozzle structure comprising nozzle members spaced from each other. to form a nozzle passage,

said-nozzle members having exterior fluidguiding surfaces disposed at relatively fi-greatradistances from the nozzle axis, said diffuser structure comprising annular diffuser members spaced from each other and having adjacent the inlet end of the diffuser passage curved fluid-guiding surfaces which with said surfaces on said nozzle structure form stream line passagescxtending axially and outwardly and decrease in cross section for delivering the fluid to be entrained to the jet issuing from said nozzle passage.

8. Ejector apparatus comprising annular diffuser and nozzle structures, said nozzle structure comprisingnoz'z'le members spaced from each other to form a nozzle passage, said nozzle members having exterior fluidguid-i'n surfaces disposed at relatively great distances from the nozzle axis, said diffuser structure comprising annular diffuser members spaced from each other and having adjacent the inlet end of the diffuser passage curved fluid-guiding surfaces which form stream line passages extending axially and outwardly and decrease in cross section for delivering; the fluid to be entrained to the jet issuing from said nozzle passage, the median planes of the'nozzle and diffuser passa es being substantially coincident and said fluid-guiding passages being symmetrical on opposite sides of saidplanes;

9. Ejector apparatus comprising annular 'dilfuser and nozzle structures, said nozzle structure comprising nozzle members spaced from each other to form a nozzle passage, said nozzle members having exterior fluidguiding surfaces disposed at relatively great structure comprising annulardiffuser members spaced from each other and havingadjacent the inlet end of the diffuser passage curved fluid-guiding surfaces which with with said surfaces on said-nozzle structure distances from the nozzle axis, said difl'user said surfaces on said nozzle structure form stream line passages delivering the fluid to be entrained to the jet issuing from said nozzle passage, said nozzle members having their maximum peripheral diameters adjacent the nozzle passage and having substantial axial width or thickness at their said maximum diameters, whereby there are formed annular dead spaces surrounding each of said nozzle members at their portions of maximum diameter.

10. Ejector apparatus compring annular difluscr and nozzle structures, said nozzle structure comprising nozzle members spaced from each other to form a nozzle passage, said nozzle members having exterior fluidguiding surfaces disposed at relatively great distances from the nozzle axis, said diffuser structure comprising annular diffuser members spaced from each other and having adjacent the inlet end of the diffuser passage curved fluid-guiding surfaces which with said surfaces on said nozzle structure form stream line passages delivering the fluid to be entrained to the jet issuing from said nozzle passage, the median planes of the nozzle and diffuser passages being substantially coincident and said fluid-guiding passages being symmetrical on opposite sides of said planes, said nozzle -members having their maximum peripheral diameters adjacent the nozzle passage and having substantial axial width or thickness at their said maximum diameters, whereby there are formed annular dead spaces surrounding each of said nozzle members at their portions of maximum diameter.

11. Ejector apparatus comprising annular diffuser and nozzle structures, said nozzle structure comprising nozzle members spaced from each other to form a. nozzlecpassage, said nozzle members having exterior fluidguiding surfaces disposed at relatively great distances from the nozzle axis, said diffuser structure comprising annular diffusef memhers spaced from each other and. having adjacent the inlet end .of the diffuser passage curved fluid-guiding surfaces which with said surfaces on said nozzle structure form stream line passagesextending axially and outwardly and decrease in cross section for delivering the fluid to be entrained to the jet issuing from said nozzle passage, said nozzle members having their maximum peripheral d1ameters ad acent the nozzle passage and having substantial axial width or thickness at their said maximum diameters, whereby there are formed annular dead spaces surrounding each of said nozzle members at their portions of maximum diameter. v v

12. Ejector apparatus comprising annular diffuser and nozzle structures, .said nozzle structure comprising nozzle members spaced from each other to form a nozzle passage,

said nozzle members having exterior fluidguiding surfaces disposed at relatively great median planes of the nozzle and difluser passages being substantially coincident and said fluid-guiding passages being symmetrical on opposite sides of said planes, said nozzle members having their maximum peri:

pheral diameters adjacent the nozzle passage and having substantial axial Width or thickness at their said maximum diameters, whereby there are formed annular dead spaces surrounding each of said nozzle members at their portions of maximum diameter.

GOTTDANK L. KOTHNY. 

